def get_bsdf(self, dgGeom: DifferentialGeometry, dgShading: DifferentialGeometry) -> [BSDF]:
dgs = DifferentialGeometry()
if self.bumpMap is None:
dgs = dgShading
else:
# todo Bump(bumpMap, dgGeom, dgShading, &dgs);
pass
bsdf = BSDF(dgs, dgGeom.normal)
r = self.Kr.get_evaluate(dgs).get_clamp()
if not r.get_is_black():
bsdf.add(SpecularReflection(r, FresnelNoOp()))
return bsdf
def EstimateDirect(scene: Scene, renderer: Renderer, light: Light, p: Point3d, n: Normal, wo: Vector3d,
time: float, bsdf: BSDF, lightSample: LightSample, bsdfSample: BSDFSample,
BxDFTypeFlag: int) -> Spectrum:
Ld = Spectrum(0.0)
visibility = VisibilityTester()
wi, Li, lightPdf = light.Sample_L1(p, lightSample, time, visibility)
if lightPdf > 0.0 and not Li.get_is_black():
f = bsdf.f(wo, wi, BxDFTypeFlag)
if not f.get_is_black() and visibility.Unoccluded(scene):
# Add light's contribution to reflected radiance
#Li *= visibility.Transmittance(scene, renderer, None)
inv_lightPdf = 1.0 / lightPdf
if light.get_is_delta_light():
Ld += f * Li * math.fabs(Vector3d.dot(wi, n)) * inv_lightPdf
else:
bsdfPdf = bsdf.get_Pdf(wo, wi, BxDFTypeFlag)
weight = PowerHeuristic(1, lightPdf, 1, bsdfPdf)
Ld += f * Li * math.fabs(Vector3d.dot(wi, n)) * weight * inv_lightPdf
# Sample BSDF with multiple importance sampling
if not light.get_is_delta_light():
wi, bsdfPdf, sampledType, f = bsdf.Sample_f(wo, bsdfSample, BxDFTypeFlag)
if not f.get_is_black() and bsdfPdf > 0.0:
weight = 1.0
if not (BxDFTypeFlag & BxDFType.BSDF_SPECULAR):
lightPdf = light.get_pdf(p, wi)
if lightPdf == 0.0:
return Ld
weight = PowerHeuristic(1, bsdfPdf, 1, lightPdf)
# Add light contribution from BSDF sampling
lightIsect = Intersection()
Li = Spectrum(0.0)
ray = Ray(p, wi, 1e-3, infinity_max_f, time)
if scene.get_intersection(ray, lightIsect):
if lightIsect.primitive.GetAreaLight() == light:
Li = lightIsect.Le(-wi)
else:
Li = light.Le(ray)
if not Li.get_is_black():
Li *= 1.0 #todo renderer.Transmittance(scene, ray, None)
Ld += f * Li * math.fabs(Vector3d.dot(wi, n)) * weight / bsdfPdf
return Ld
def get_bsdf(self, dgGeom: DifferentialGeometry, dgShading: DifferentialGeometry)->[BSDF]:
dgs = DifferentialGeometry()
if self.bumpMap is None:
dgs = dgShading
else:
#todo Bump(bumpMap, dgGeom, dgShading, &dgs);
pass
bsdf = BSDF(dgs, dgGeom.normal)
r = self.Kd.get_evaluate(dgs).get_clamp()
sig = get_clamp(self.sigma.get_evaluate(dgs), 0.0, 90.0)
if r.get_is_black():
bsdf.add(OrenNayar(r,sig))
else:
bsdf.add(Lambertian(r))
return bsdf
def get_bsdf(self, dgGeom: DifferentialGeometry, dgShading: DifferentialGeometry)->[BSDF]:
dgs = DifferentialGeometry()
if self.bumpMap is None:
dgs = dgShading
else:
#todo Bump(bumpMap, dgGeom, dgShading, &dgs);
pass
bsdf = BSDF(dgs, dgGeom.normal)
kd = self.Kd.get_evaluate(dgs).get_clamp()
if not kd.get_is_black():
diff = Lambertian(kd)
bsdf.add(diff)
ks = self.Ks.get_evaluate(dgs).get_clamp()
if not ks.get_is_black():
fresnel = FresnelDielectric(1.5, 1.0)
rough = self.roughness.get_evaluate(dgs)
spec = Microfacet(ks, fresnel, Blinn(1.0 / rough))
bsdf.add(spec)
return bsdf
